@sap/cds-dk/lib/util/question.js

Command line client and development toolkit for the SAP Cloud Application Programming Model

const readline = require('node:readline')
const { Writable } = require('node:stream')

async function ask4([...args], { redacted = false } = {}) {
  var mutableStdout = new Writable({
    write: function (chunk, encoding, callback) {
      if (!redacted)
        process.stdout.write(chunk, encoding);
      callback();
    }
  });

  // If not in interactive mode, read all input at once.
  if (!process.stdin.isTTY) {
    const data = await new Promise(resolve => {
      let result = ''
      process.stdin.on('data', chunk => result += chunk)
      process.stdin.on('end', () => resolve(result))
    })
    return data.split(/\r?\n/).slice(0, args.length)
  }

  const answers = []
  const rl = readline.createInterface({
    input: process.stdin,
    output: mutableStdout,
    terminal: true
  })

  const askQuestion = question =>
    new Promise(resolve => {
      if (redacted && process.stdin.isTTY) {
        // Set raw mode to intercept keystrokes
        process.stdin.setRawMode(true)
        process.stdout.write(question)

        let answer = ''
        const onData = (char) => {
          const byte = char.toString()

          // Enter key
          if (byte === '\n' || byte === '\r') {
            process.stdin.setRawMode(false)
            process.stdin.removeListener('data', onData)
            process.stdout.write('\n')
            answers.push(answer)
            resolve()
          }
          // Backspace/Delete
          else if (byte === '\b' || byte === '\x7f') {
            if (answer.length > 0) {
              answer = answer.slice(0, -1)
              process.stdout.write('\b \b')
            }
          }
          // Ctrl+C
          else if (byte === '\x03') {
            process.stdin.setRawMode(false)
            process.exit()
          }
          // Regular character
          else if (byte >= ' ' || byte === '\t') {
            answer += byte
            process.stdout.write('*')
          }
        }

        process.stdin.on('data', onData)
      } else {
        rl.question(question, answer => {
          answers.push(answer)
          resolve()
        })
      }
    })

  for (const question of args) {
    await askQuestion(question)
  }
  rl.close()
  return args.length == 1 ? answers[0] : answers
}

module.exports = { ask4 }